Aqueous humor levels of vascular endothelial growth factor in retinitis pigmentosa

PURPOSE. To determine the level of vascular endothelial growth factor A (VEGF-A) in aqueous humors of patients with retinitis pigmentosa (RP). METHODS. A prospective, comparative control study. Aqueous humor was collected from 16 eyes of 16 patients with RP. The level of VEGF-A was determined with a commercially available enzyme-linked immunosorbent assay kit. The control group comprised 16 aqueous samples from 16 patients about to undergo cataract surgery and without any other ocular or systemic diseases. RESULTS. The concentration of VEGF-A in aqueous humor was markedly lower in patients with RP than in control subjects (Mann-Whitney U test, P < 0.001). The level of VEGF-A was 94.9 +/- 99.8 (mean +/- SD) pg/mL in eyes with RP and 336.5 +/- 116.8 pg/mL in the eyes of the control group. CONCLUSIONS. In patients with RP, the concentration of VEGF-A in aqueous humors is lower than in non-RP subjects. The lack of angiogenic actions attributed to VEGF-A may explain some of the clinical manifestations of this disease, such as narrowing and fibrotic degeneration of retinal blood vessels.